MHT CET2016PhysicsExperimental Physics
In balanced meter bridge, the resistance of bridge wire is 0.1 Ω cm. Unknown resistance X is connected in left gap and 6 Ω in right gap, null point divides the wire in the ratio 2 : 3 . Find the current drawn from the battery of 5 V having negligible resistance.
Options
- A1 A
- B1.5 A
- C2 A
- D5 A
Correct answer
A. 1 A
Step-by-step solution
l 1 l 2 = 2 3 = v 1 v 2 Now v 1 + v 2 = v = 5 V = I R For potentiometer wire R 1 R 2 = l 1 l 2 = 2 3 x 6 = 2 3 ⇒ x l = 4 Ω m The resistance of wire is 0.1 Ω c m = 1 Ω m ∴ x + 1 = R e f f = 5 ∴ i = V R e f f = 5 5 = 1 A